The present invention relates to a disposable diaper excellent in leak-preventive property and capable of preventing leak occurrable particularly around the leg areas. This invention also relates to a disposable diaper excellent in storability/retainability of an auxiliary absorber, wearability (property of feel in wear and easy application to a wearer) and/or fitness at the crotch region and the like, in addition to its excellent leak-preventive property.
Heretofore, it has been a significant problem for disposable diapers as to how to prevent leaks from occurring around the leg areas. Japanese Patent Publication No. 05-33630 discloses a disposable diaper in which an absorbent core is comprised of a central absorbent section of a width in conformity with the human body and an outer absorbent section disposed outside thereof, so that a close fit to a wearer at the crotch region is enhanced, thereby improving the leak-preventive property. However, this disposable diaper has the problem that wrinkles can occur in the central absorbent section due to the contraction of an expansible part placed between the central absorbent section and the outside absorbent section, whereby urine and excretions can easily leak from the central absorbent section along the wrinkles. Moreover, since it is designed such that leaks are prevented by enhancing the fit at the central absorbent section, urine and excretions which leak out towards the opposite sides from the central absorbent section can reach the outside absorbent section comparatively easily, and especially, in the case where the amount of excretions is large, the feces and urine easily leak outside beyond the outside absorbent section.
Moreover, since the outside absorbent section is difficult to conform along the contour of the wearer's body, the wearability and fitting property at the crotch region deteriorate.
Japanese Patent No. 2712044 discloses a disposable diaper in which three-dimensional guards each composed of an absorbent material are disposed at the outside of the an absorbent core in a longitudinal direction thereof. This diaper also has the same problem as the above-mentioned disposable diaper.
Another problem of the disposable diaper of Japanese Patent Publication No. 05-330630 is that it is not easy for a wearer to put it on because this diaper does not deform to the curved configuration of the wearer's body at the time of putting it on.
In the disposable diaper of Japanese Patent Publication No. 05-33630, the outside absorbent section is brought into contact with the inner side of the wearer's upper thigh. However, in this disposable diaper, the outside absorbent section is liable to be turned over at an area in the vicinity of the boundary area between the stomach side region and/or the back side region where the central absorbent section and the outside absorbent section are placed on a same plane and brought into contact with the wearer and the crotch region where the outside absorbent section and the central absorbent section are greatly bent, and leaks may occur through a gap formed between the outside absorbent section and the wearer's skin. Moreover, it is difficult for the disposable diaper to sufficiently fit with the outside absorbent section to the inner side of the wearer's upper thigh. In short, in conventional disposable diapers, sufficient leak-preventive property is not yet realized even for those of the type in which an absorbent core is disposed around the leg area.
Recently it was suggested, in order to reduce the economical/laborious burden in nursing work or the like, that an auxiliary absorber be used in combination with a disposable diaper. Howver, the conventional disposable diaper experiences deterioration in storability/retainability of the auxiliary absorber and thus its improvement is demanded.
Japanese Patent Application Laid-Open No. 01-119250, Japanese Utility Model Application Laid-Open No. 04-67427 and Japanese Utility Model Application Laid-Open No. 02-18824 disclose disposable diapers having a side absorbent core. However, even in those disposable diapers, the side absorbent core cannot fit to the wearer's leg area sufficiently. Furthermore, even in disposable diapers disclosed in Japanese Patent Application Nos. 03-121069 and 03-123553, sufficient leak-preventive property cannot be achieved.